1. Field of the Invention
The present invention relates to a method of executing services on a network and to a flow processing apparatus.
2. Description of the Related Art
In cases where a flow processing apparatus causes a service execution apparatus to execute a plurality of services using a flow description document, the general practice conventionally is to describe the services of the service execution apparatus that has been connected to the same network as that of the flow processing apparatus.
For example, the specification of Japanese Patent Application Laid-Open No. 2005-173892 discloses a service linkage processing system for dividing service linkage processing into a plurality of processes and creating subroutine designation documents of the individual processes and a main routine designation document in which content for controlling the execution of each subroutine designation document is described.
However, in cases where flow processing that utilizes individual services placed on two networks isolated by a firewall is described in a flow description document, the following problem arises:
For example, if a firewall is set up so as to allow communication from a specific address to a specific address and the security level is lowered, the flow processing apparatus may then send a command directly to the service execution apparatus. However, since a setting that lowers security level must be directed to all services placed on the inner side of the firewall, it is necessary to change the firewall settings whenever the flow description document is redefined.
At the time of operation, and in particular, when a new flow description document is executed, it is necessary that the network environment such as the firewall be configured again.
Further, although a protocol (e.g., SMTP) that makes it possible to pass through a firewall can be utilized in communication from the flow processing apparatus to the service execution apparatus, the protocol utilized by the service generally is HTTP. As a consequence the following problem arises:
In a service execution apparatus utilized from a flow processing apparatus, it is necessary to perform a change of settings in such a manner that processing will be capable even with Simple Mail Transfer Protocol (SMTP). When a flow description diagram is executed anew, it is necessary to reconfigure the network environment at the time of operation.